West Nile Virus

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What Is West Nile Virus?

Also called: West Nile Fever, West Nile Disease

West Nile virus is a mosquito-borne viral disease. The disease
is transmitted to humans and animals when they are bitten by an infected
mosquito. The mosquito acquires the virus in the first place by feeding on
infected birds. Only certain species of mosquito can carry West Nile virus.

There have been a few reported cases of West Nile virus transmission from organ
transplants or blood transfusions.

Transmission to a child from a mother who has the disease also is possible during
pregnancy, and through breastfeeding. This has been documented in a very small
number of cases.

West Nile virus is not transmitted through casual contact. You cannot get
West Nile virus from touching or kissing a person who is infected.

West Nile disease was first detected in the Western Hemisphere in the summer of
1999, during an outbreak in New York City. Since then it has spread throughout
the continental United States, and to some parts of Canada and the Caribbean.

Although a number of people die each year as a result of West Nile virus infection,
death in humans is still relatively uncommon. In fact, many people who become
infected have very mild symptoms, or none at all.

West Nile virus can be serious for certain individuals, especially older people, the
very young, and those with other medical conditions. In serious cases, the
virus causes inflammation of the brain and/or the membranes that surround the brain
and spinal cord. This invasion of the central nervous system can lead to
paralysis and possibly death.

Unfortunately there is no sure way to know ahead of time whether or not you'll get
sick if you become infected.

Risk Factors for West Nile Virus:

People who spend a lot of time outdoors are more likely to be bitten by
mosquitoes, including the types that carry West Nile virus.

Visiting or living in geographic regions where mosquito-borne viruses are
prevalent increases your risk of being bitten by a mosquito with West Nile
virus. The U.S. Centers for Disease Control website provides a
map for monitoring West Nile virus activity in the United
States.

The risk of West Nile virus is seasonal, to a certain degree. The
number of cases tends to rise seasonally, beginning in late spring, and peaks in
late summer and early fall.

Mosquitoes -- including the types that can carry West Nile virus -- breed in
standing water. Thus, the risk for West Nile disease is greater in
areas with a lot of standing water, such as ponds and swamps.

Treatment for West Nile Virus:

If you become ill and suspect that you may have West Nile virus, your doctor can
confirm this through a blood test.

There is no specific treatment for West Nile virus, and mild cases usually run their
course in a matter of days, leaving no after-effects.

Serious cases usually require hospitalization. The patient is given supportive
therapy such as intravenous fluids and pain relievers. The most serious cases
may need to be managed in an intensive care unit. Patients seriously ill from
West Nile virus may need to be put on a ventilator to aid their respiration.

Prevention of West Nile Virus Infection:

Avoiding the West Nile virus hinges on eliminating mosquito breeding sites, and
avoiding or reducing exposure to mosquitoes so that you will not be bitten.

To eliminate mosquito breeding sites:

empty unused swimming pools and wading pools

be sure that your roof gutters are not clogged

remove old tires, flower pots, planters, buckets, barrels, and other containers
in your yard that can collect water

change water frequently in outdoor pet bowls, birdbaths, etc.

To reduce your exposure to mosquitoes:

spend as little time as possible outdoors during dawn, dusk, and early evening
hours when mosquitoes are most active

wear long-sleeved shirts and long pants (even if it is warm!) when you are in
an area where there are a lot of mosquitoes

use insect repellent that contains the active ingredient
Picaridin, or a 10% to 30% concentration of DEET and spray your clothing
as well as exposed skin. Read and follow the directions on the label

be sure that screens on windows and doors are in good repair

cover your infant's playpen, crib or stroller with mosquito netting

A Final Note:

West Nile virus is harbored in wild birds. If you find a dead bird, do not
pick it up or handle it with your bare hands.&nbsp
Report it to your local health
department. They will advise you on how to dispose of it.

References:

In the interest of facilitating further research on the topic of West Nile Virus,
we have compiled a list journal articles and other references related to the
topic. We also include a section of references regarding
Mosquito
Repellents.

Some of the items listed here were used as source material to prepare this information
page about West Nile Virus.